The present invention pertains to a control system for a motor driven door operator, primarily intended for industrial type doors, including sectional upward acting or rollup doors, gates and similar closures, and methods of controlling the door operator.
Motor operated doors particularly adapted for industrial applications desirably include motor controls which facilitate ease of operation of the door and provide for a long operating life in rigorous operating conditions. One type of door operator that has been developed for use with the present invention is operable to be driven by electric motors and may be adapted to automatically close in the event of a power failure or upon receiving a remote control signal, be manually operated to open or close and be adapted for use with motors of various power capacities and electric power sources. Still further, the operating requirements for commercial or industrial doors and gates have dictated other improvements in control systems for motor operated closures, including upward acting doors, in particular. The present invention provides certain improvements needed in this art.
The present invention provides an improved door operator control system for controlling a motor driven operator for doors, gates and upward acting doors, in particular.
In accordance with one aspect of the present invention a control system is provided which includes a programmable microcontroller and associated control circuits and is adapted for use with door operators driven by electric motors of various power capacities and power sources. The control system includes protective circuit elements to avoid damage to the control system caused by power source voltage transients, including overvoltages resulting from connection of a transformer of the wrong voltage rating, or major voltage surges such as induced by nearby lightning strikes.
In accordance with another aspect of the present invention a door operator control system is provided which includes improvements in circuitry for receiving signals indicating door travel limits, an advantageous arrangement of operator control elements for controlling a microcontroller unit of the control system and circuits for input signals from various sources including external interlock input signals and remote control input signals.
The control system of the present invention also includes circuits for connecting a microcontroller to motor drive relays or contactors including an interlock feature, a motor drive xe2x80x9cwatchdogxe2x80x9d circuit, a motor drive status feedback circuit, control circuitry for controlling a door operator which includes an operator brake, and an emergency operator shutdown circuit.
The control system of the present invention further includes a keypad for inputting control signals and calibration signals to a microcontroller via a serial communication bus to control door functions including door overrun of a position limit, braking rate of the operator brake, a mid position stop, clearing maximum run timers of the operator and correlating the motor direction of rotation with door direction of movement. The control system further includes a seven segment display and calibration indicators for displaying a condition code in the normal operating mode of the control system, calibration information when the control system is being operated in a calibration mode and error codes indicating a fault or error condition existing in the control system and the associated operator. The seven segment display includes a driver circuit including a multiplexed constant current source.
The present invention still further provides an improved method of operating a motor driven operator for opening and closing a closure device, such as an upward acting sectional or rollup door or a gate wherein improved braking action is imposed by and on the operator to control a braking rate of the door to minimize shock loads, wear and tear on the door and the operator, and to reduce noise associated with door operation.
The control system is also adapted to provide a method of operation which allows a door position limit overrun with variable progressively longer or shorter time delays between the time that a limit position is achieved and the door operator begins a braking procedure. In particular, when the door operator activates a switch determined to be the door down position limit switch, a user selectable time delay may be input to the controller, which time delay will delay motor shutdown and the onset of the braking procedure to allow the door bottom edge to seal against a floor or sill and without activating a door reversal or so-called safety reversal switch, which would otherwise cause an unintended reversal of the door.
Those skilled in the art will further appreciate the features and advantages of the door operator control system and method of operation as well as other important aspects thereof upon reading the detailed description which follows in conjunction with the drawings.